Study on structure, microstructure and microwave dielectric characteristics of CaV₂O₆ and (Ca_0.95M_0.05)V₂O₆ (M=Zn, Ba) ceramics

Abstract

In this study, the (Ca0.95M0.05)V2O6 (M = Zn, Ba) and the CaV2O6 ceramics were synthesized through a solid‐state reaction method, and the effects of Zn2+ and Ba2+ substitution on the structure, sintering temperature, densification, microstructure and microwave dielectric properties of CaV2O6 ceramic were analysed. The XRD patterns of the sintered samples indicated a single‐phase of CaV2O6 in all temperatures. Substitution of Zn2+ caused a lower sintering temperature and improved the densification of the CaV2O6 ceramic. While the dielectric properties of the (Ca0.95Ba0.05)V2O6 compound were not desirable, the (Ca0.95Zn0.05)V2O6 sample sintered at 650°C for 4 hours showed significant dielectric properties, with εr = 10.29, Q × f ~ 53 000 GHz (at 15.5 GHz) and τf = −72.37 ppm/°C. Moreover, the chemical compatibility of the CaV2O6 ceramic with Al electrode was examined.

Low Temperature Sintering, Structure and Microwave Dielectric Properties of Novel (1 – x)MgGa2O4–xCuMoO4 Ceramics for LTCC Applications

“…35 To further study the material structure, the Raman spectra of (1 − x)MgGa 2 O 4 −xCuMoO 4 (x = 0.2−0.6) are shown in Figure 8. According to group theory, CuO has the (Ag +2Bg) Raman activity mode, 36 288 cm −1 corresponds to Ag, and 348 38 There are five Raman activity modes (A 1g (R) + E g (R) + 3T 2g (R)) in the MgGa 2 O 4 phase. 39 The observed four band energies in this study contain the signals generated by the lattice vibrations shown in Figure 8a, which are assigned to these Raman active vibrational modes.…”

“…To further study the material structure, the Raman spectra of (1 – x )­MgGa 2 O 4 – x CuMoO 4 ( x = 0.2–0.6) are shown in Figure . According to group theory, CuO has the (Ag +2Bg) Raman activity mode, 288 cm –1 corresponds to Ag, and 348 cm –1 is the vibration mode of B g . The bands of 813, 833, 941, and 976 cm –1 correspond to the stretching vibration mode of the [MoO 4 ] tetrahedral structure of CuMoO 4.…”

Phase transition mechanism and long‐term stability of LiF‐assisted sintered Li2MgxZrO3+x microwave dielectric ceramics

“…4,5 However, with a gradual increase in mobile communication frequency bands, the exploitation of ceramics with excellent microwave dielectric properties (MDPs), low sintering temperatures (≤ 950 • C), and excellent chemical compatibility with silver electrodes is a matter of extreme urgency. 6,7 Li 2 ZrO 3 is an important functional material for a wide range of applications, such as nuclear fusion, 8 lithium batteries, 9 CO 2 absorbers, 10 etc. Recently, the rock-salt structured Li 2 ZrO 3 system has attracted extensive attention due to its excellent and adjustable MDPs.…”

“…In addition, low‐temperature co‐fired ceramic (LTCC) technology plays a crucial role in the miniaturization, integration, and modularization of multilayer devices 4,5 . However, with a gradual increase in mobile communication frequency bands, the exploitation of ceramics with excellent microwave dielectric properties (MDPs), low sintering temperatures (≤ 950°C), and excellent chemical compatibility with silver electrodes is a matter of extreme urgency 6,7 …”

Low-temperature sintering, dielectric performance, and far-IR reflectivity spectrum of a lightweight NaCaVO4 with good chemical compatibility with silver

“…The intensively explored low-sintering materials mainly include Li2O, Bi2O3, TeO2, MoO3, WO3, and V2O5 [13][14][15][16][17][18][19]. Recently, vanadates have attracted considerable attention for their potential applications in LTCC in consideration of their low molten point and outstanding microwave dielectric properties [20][21][22][23][24]. For example, Yao et.…”